Im looking to make a unique take on the american wheat style. I want to make it with carawheat instead of crystal/caramel malt and a touch of roasted malt for color. I was also thinking about using wheat malt as the base but I didnt know if you could brew with essentially 100% wheat. Can this be done or would I need at least a little 2-row or Pils Malt for it?

I think you need two-row/six-row with diastatic power in order to convert the starches to sugars. I want to say that you can go 50/50 with it like in a wheat wine or a Wit. I'm not sure what the breaking point is for the ratio, but I would imagine that if you want less base malt and more wheat, then it would be better to use six row since it has a bunch more diastatic power.

It depends if you are thinking actual wheat malt or something like flaked malt. I am not sure if the first has diastatic power, and I know the second does not.

I did a little research, and it depends on which wheat malt base you want to use. White wheat malt is the only one to have enough diastatic power to completely convert itself (130%). German wheat malt is really close at 95%, dark wheat is 10%, and Belgian wheat malt is 74% for the set of malt analyses that I looked at. It is suggested to "Use with a highly modified malt to insure diastatic enzymes. (http://www.foamrangers.com/malts.html)" though the same people list that common German Weizens are up to 70% wheat malt. Hope that helps.

Look at the malt analysis of the wheat malt you plan to use. If it is 100% or more it should convert itself in theory, though most things I see when I search around suggest using at least some base malt in the mash with high enzymatic power.

+1, diastatic power is measured in degrees lintner, not percent. Malted Wheat & Malted rye have enough DP to convert themselves and plenty more to spare. I think I remember hearing on Brew Strong in the Malt episode it's a level of 50 Lintner that'll be enough to convert.

You can figure total mash DP in a similar general way that you add up gravity points in your grist too:

Add up the Lintner contribution of each individual malt in terms of their weights, then divide by the total weight.Sum of (X lbs of malt * Y Degrees Lintner for that malt) / (total lbs of malt)

The guys that are doing Mini-Mashes can use this formula to figure out how much base malt they need to add so that they can convert their batches. This is especially crucial for things like a mini-mash Classic Am. Pilsner. You basically need to work the numbers backwards:

50 linter must equal the sum of the (weights * deg lintner) / sum of the weightsWe don't know how much pilsner malt to add, so say that its weight is X.